While they have English skills, they aren't immersed in American culture and might misunderstand the humor, even if it is labeled satire.
They don't and nor should they. It's a Western centric concept and for most of the world were it has no relevance it's hard to understand.
(You might argue all incidents like that should be taught in all schools, but until the West starts they can't expect anyone else to care about their bugbears)
For example -
Genocides: The holocaust, Rwandan genocide, Armenien genocide, etc.
Empires: British, Mongol, Roman etc.
Wars: WWII, WW1, Mongol Wars, etc.
Fastest expanding empires, Most peaceful periods, Most scientifically productive periods, etc.
Never heard about Armenian and Rwandan genocides until college.
Does the same happen to The Onion?
It's why fact checking just can't work. There's too much bias in people.